102
5 Handling Uncertainty and Sensitivity …
Table 5.6 Summary of assessments or calculations used as basis for classification in the shoreline.
Lag-time and recovery parameters
Main parameter
A: Strength of knowledge (function where it is used)
B: Belief that the value may deviate from the average assumption (natural
variation of parameter)
C: Sensitivity of function to parameter (sensitivity index)
Lag-time
A Moderate/low. Due to lack of experience data, it is challenging to assign
specific lag-time periods for shorelines
B High/moderate. Variable and to a large degree depending on weather
conditions
C High
Comments/recommendations:
Fixed look-up values
Recovery
A Moderate/low. Due to lack of experience data, it is challenging to assign
specific restitution time periods for shorelines
B High
Variable depending on invertebrate and flora communities
C High
Comments/recommendations:
Fixed look-up values
Table 5.7 Summary of assessments or calculations used as basis for classification in the seafloor.
Impact parameters
Main parameter
A: Strength of knowledge (function where it is used)
B: Belief that the value may deviate from the average assumption
(Natural variation of parameter)
C: Sensitivity of function to parameter (sensitivity index)
Mixing depth
A Strong/moderate. Knowledge of what constitutes the bioturbation
depth is relatively strong
B High uncertainty
C 40.0% high
Comments/recommendations: A lower value is conservative, lower
values are default for all substrates based on size of typical burrowing
fauna in substrate. High natural variation: Either look for local real
values or use conservative value
Dry density
A Strong
B Low
C 0.5% low
Comments/recommendations: Schultz and Zabel (2006) give
general values. Low sensitivity, use defaults
Water Content
A Strong
B Low/moderate
C 2.7% low
Comments/recommendations: Use lower values as conservative
Total org. Carbon
A Strong (EqP accepted methodology)
B High
C 54.9% high
Comments/recommendations: Use conservative (lower) values.
Lower values lead to higher toxicity and shorter restoration times
(Higher TOC sequesters THC in sed.)
(continued)
5 Handling Uncertainty and Sensitivity …
Table 5.6 Summary of assessments or calculations used as basis for classification in the shoreline.
Lag-time and recovery parameters
Main parameter
A: Strength of knowledge (function where it is used)
B: Belief that the value may deviate from the average assumption (natural
variation of parameter)
C: Sensitivity of function to parameter (sensitivity index)
Lag-time
A Moderate/low. Due to lack of experience data, it is challenging to assign
specific lag-time periods for shorelines
B High/moderate. Variable and to a large degree depending on weather
conditions
C High
Comments/recommendations:
Fixed look-up values
Recovery
A Moderate/low. Due to lack of experience data, it is challenging to assign
specific restitution time periods for shorelines
B High
Variable depending on invertebrate and flora communities
C High
Comments/recommendations:
Fixed look-up values
Table 5.7 Summary of assessments or calculations used as basis for classification in the seafloor.
Impact parameters
Main parameter
A: Strength of knowledge (function where it is used)
B: Belief that the value may deviate from the average assumption
(Natural variation of parameter)
C: Sensitivity of function to parameter (sensitivity index)
Mixing depth
A Strong/moderate. Knowledge of what constitutes the bioturbation
depth is relatively strong
B High uncertainty
C 40.0% high
Comments/recommendations: A lower value is conservative, lower
values are default for all substrates based on size of typical burrowing
fauna in substrate. High natural variation: Either look for local real
values or use conservative value
Dry density
A Strong
B Low
C 0.5% low
Comments/recommendations: Schultz and Zabel (2006) give
general values. Low sensitivity, use defaults
Water Content
A Strong
B Low/moderate
C 2.7% low
Comments/recommendations: Use lower values as conservative
Total org. Carbon
A Strong (EqP accepted methodology)
B High
C 54.9% high
Comments/recommendations: Use conservative (lower) values.
Lower values lead to higher toxicity and shorter restoration times
(Higher TOC sequesters THC in sed.)
(continued)